With the dervation of human embryonic stem (hES) cells, and the subsequent limitation of eligibility for federal funding to those lines derived prior to August 9, 2001, the efficient distribution of the eligible lines is of primary importance. This proposal seeks to achieve this goal through three aims. Aim 1: First, The hES cells derived at University of California, San Francisco (UCSF), HSF-6 and HSF-1 will be expanded in large lots, tested for sterility, hES cell characteristics, and differentiation potential; for distribution to academic facilities throughout the world. Sublines of hES lines selected for useful characteristics, such as expression of green fluorescent protein and high levels of expression of hES cell-surface markers will also be derived for distribution. A website will provide users with information about the cell lines, and order forms. Aim 2: Secondly, a training program will be initiated for qualified technical staff to provide recipient labs with the expertise necessary to successfully establish hES cultures in their own lab. Finally, the hES cell lines available at UCSF will be gradually transferred to cultures incorporating good laboratory practices, including extensive testing and documentation of the history of the cells and culture conditions the lines have encountered. Achievement of these aims will provide users with the valuable tools necessary to perform innovative studies of human development and generation of tissues for human transplantation.